Youcat commented through CCC - Question n. 62 Part I.

YOUCAT Question n. 62 Part I. - What is the soul?

(Youcat answer) The soul is what makes every individual person a man: his spiritual life-principle and inmost being. The soul causes the material body to be a living human body. Through his soul, man is a creature who can say “I” and stand before God as an irreplaceable individual.      

A deepening through CCC

(CCC 362) The human person, created in the image of God, is a being at once corporeal and spiritual. The biblical account expresses this reality in symbolic language when it affirms that "then the LORD God formed man of dust from the ground, and breathed into his nostrils the breath of life; and man became a living being"(Gen 2:7) Man, whole and entire, is therefore willed by God. (CCC 363) In Sacred Scripture the term "soul" often refers to human life or the entire human person (Cf. Mt 16:25-26; Jn 15:13; Acts 2:41). But "soul" also refers to the innermost aspect of man, that which is of greatest value in him (Cf. Mt 10:28; 26:38; Jn 12:27; 2 Macc 6: 30), that by which he is most especially in God's image: "soul" signifies the spiritual principle in man. 362  363

Reflecting and meditating 

(Youcat comment) Men are bodily and spiritual creatures. A man’s spirit is more than a function of his body and cannot be explained in terms of man’s material composition. Reason tells us that there must be a spiritual principle that is united with the body but not identical to it. We call it the “soul”. Although the soul’s existence cannot be “proved” scientifically, man cannot be understood as a spiritual or intellectual being without accepting this spiritual principle that transcends matter.    

(CCC Comment)

(CCC 364) The human body shares in the dignity of "the image of God": it is a human body precisely because it is animated by a spiritual soul, and it is the whole human person that is intended to become, in the body of Christ, a temple of the Spirit (Cf. 1 Cor 6:19-20; 15:44-45): Man, though made of body and soul, is a unity. Through his very bodily condition he sums up in himself the elements of the material world. Through him they are thus brought to their highest perfection and can raise their voice in praise freely given to the Creator. For this reason man may not despise his bodily life. Rather he is obliged to regard his body as good and to hold it in honor since God has created it and will raise it up on the last day (GS 14 § 1; cf. Dan 3:57-80).    

(This question: What is the soul? is continued)