The purpose of this section of the dissertation is to assess the minimum level of certitude for the thesis proposed, with
an additional comment of any suspected higher level of certitude. There are various levels of certitude that can be chosen.
Opinion is defined as intellectual assent (or disagreement) given to one part of a contradiction with fear of the opposite.99
Possibility is defined as the capacity for existence for a concrete possible thing: internally, that its constituent characteristics
are not impossible, and additionally externally possible, if there is power to produce the thing.100 Probability,
also called likelihood, is defined as the weight of motives, or the accumulation of serious motives, for prudent assent to
some proposition, which is intrinsic probability if the motive arises from the nature of the thing, and can be extrinsic probability
if the motive is from authority, which can also suppose the internal motive.101 Summary of Probabilities is defined
as an accumulation of probable arguments, considered according to their force, which results from a mere juxtaposition. Convergence
of Probabilities is defined as an accumulation of probabilities which converge to produce a sufficient reason. Moral certitude
is defined as firm assent to one part of a contradiction whose necessity arises from the moral law in the physical (not ethical)
sense, e.g., every mother instinctively loves. Physical certitude is defined as firm assent to one part of a contradiction
whose necessity arises from the very physical nature of the thing, e.g., the law of gravity. Metaphysical certitude is defined
as firm assent to one part of a contradiction whose necessity arises from metaphysical necessity, e.g., my own existence.
Certitude could arise from some observable fact or experiment. There is no experiment to prove evolution.102
However, some restricted observation of evolution is possible within species and as a biological ascent.103 Further,
in art, finality is evident as the goal of the artist.104 Proof of the principle of finality, noted by Aristotle,
is observed from the regularity in nature, is observed from art imitating nature, and from adaptation of plants and animals
that can be observed in nature.105 Concerning a metaphysical proof, Gardeil cites Aquinas that movement must have
a goal.106 Concerning irrational creatures, St. Thomas notes: "The entire irrational world is related to God as
an instrument is to a principle agent (Aquinas Summa Theologiae 1-2. 1. 2).107
Certitude could arise from some philosophical explanation that exists for the need of concept of finality in Evolutionism.
Explanations were given by several Neo-Scholastics, notably Klubertanz, who gave a detailed explanation of how finality works
in evolution.108 His view on finality was supported by Calcagno, De Finance, Dougherty, Donat, Gardeil, Glenn,
Hugon, La Vecchia, and Renard. Klubertanz’s view of chance in Evolutionism was supported by Ayala, De Finance, and Nogar.
Klubertanz’s view of Providence in Evolutionism was supported by Benignus and Haffner. That chance and Providence work
together in Divine Concursus was supported by Benignus and Hellin.
Certitude could arise if the argumentation was based on some philosophical principles. Two arguments for finality in Evolutionism
were given, one based on the principle of finality and the other based on the principle of sufficient reason.
Certitude could arise if the explanation is sufficient, due to the principle of sufficient reason. But the explanation
Certitude could arise if the explanation was rooted in St. Thomas Aquinas, thereby being faithful to tradition. St. Thomas
has a theory of biological ascent (Aquinas Summa Contra Gentiles 3. 22) that approaches programmed evolution.
Certitude could arise if Neo-Scholastics agree on the possibility of the principle of finality as universally applicable,
including applicability to Evolutionism. The Neo-Scholastics and their philosophical predecessors do agree.110
Certitude could arise due to recent scientific confirmation by convergent scientific arguments. Science has found that
during the process of mitosis (for single-celled living things) and the process of meiosis (in bisexual reproduction), living
things are particularly susceptible to outside interference, which is equivocal causality.111 Confirmation of equivocal
causality is from Stephen Scherer of the Hospital for Sick Children in Toronto who has identified 1,576 apparent random mutations
between the genome of the chimpanzee and the human; more than half occurred sometime during human evolution.112
Certitude could arise if the opposite opinion is not tenable. The opposite opinion would be a denial of the principle of
finality, which is not possible since the principle of finality is an analytic principle, universal and necessary.113
Certitude could arise if the objections of adversaries are able to be answered.
OBJECTION: To act toward a goal demands knowing the goal. But natural agents cannot know the goal. Therefore, natural agents
cannot act for a goal. REPLY: Rational agents can act for a goal, formally and self-directing. Irrational agents can act for
a goal, materially and executively, as something directed by another toward a goal, just as the arrow was shot at the target
by the bowman.114
OBJECTION: The goal of an action, finality, is only attained at the end of the act. REPLY: The goal is first in order of
intention, and last in order of execution.115
OBJECTION: Some Neo-Scholastics have said evolution is impossible, because of the principle of causality: the effect cannot
be more perfect than the cause. REPLY: This can be answered by the theory of equivalent causality. There are multiple causes.
OBJECTION: Some Neo-Scholastics have said evolution is impossible, because of the principle of causality: the effect must
be the same kind as it non-cognoscitive cause. REPLY: This can be answered by the theory of equivalent causality. There are
OBJECTION: Observable nature presents no signs of purpose or finality. REPLY: This conclusion is far from self-evident.
Even the survival of the fittest in the struggle for existence has life itself as the end and goal of the struggle.116
OBJECTION: The chief criticism leveled at the evolutionists is based on their tendency to forget that not all evolution
means progress.117 REPLY: The theory of equivocal causality of Klubertanz is adequate enough to explain regressive
evolution.118 "Regressive evolution" is that type of evolution in which the offspring would be essentially less
perfect than the parent, and on the scientific level an example are parasites.
Certitude can be had from the possibility of philosophers and theologians admitting this mode of origin without damage
to their other beliefs.119
The level of certitude for "Evolutionism needs some concept of purpose," is at minimum at the level of the metaphysically
certain. The proof is the principle of finality, which is an analytic principle, universal and necessary.120 Further,
the convergence of all of the above arguments are proof, especially the fulfillment of the principle of sufficient reason.
This agrees with the opinion of Hellin, who rates this thesis "most certain."121
Having come to the correct conclusion on the philosophical level of certitude, the philosopher must still conclude with
some humility. The philosophy of nature still presents some problems, even for the philosopher. First, nature is unquestionably
endowed with finality. But that is not to say that one can always identify the specific end of each thing and each activity
in nature.122 Second, when the principle "every agent acts for an end" (omne agens agit propter finem) is
rigorously applied, it is to the nature, and not to the individual as such. We do not want to assign to each event a distinct
finality when we say "natura nihil facit frustra" (Aquinas De Anima 3. 1. 17). The opaqueness proper to material
explains the imperfect intelligibility of facts.123 Third, nature is a complex reality, and the whole explanation
of its course and events must be sought in all the causes. To produce a certain kind of thing, it will be necessary to use
a certain kind of material; or, this kind of agent must be had to perform this kind of work. The attainment of the final goal,
then, does depend, in some manner and measure, on the matter and the other pre-existing causes. The end is the principle cause
and condition to which all other causes are subordinate and secondary. Whatever the material, formal and efficient causality
contribute to a thing they do so by virtue of the final cause; and inversely, whatever a thing owes to them, it owes still
more to the final cause. St. Thomas says, "The philosopher of nature should give both causes, namely the material and the
final, but more the final, because the end is the cause of the matter but the opposite is not true. It is not true that the
end is such because the matter is such, but rather the matter is such because the end is such" (Aquinas In Phys. 2.