Thomas Aquinas isn’t as fashionable as other modern philosophers. J.P. Sartre’s philosophy criticized his mode of being through Hegel without knowing it. Existentialism was almost totally ignorant of their ‘tenets.’
So what is it that the existentialists missed? He speaks of God naturally, which must irritate many people. But God is, above all, the ultimate being, the cause, the intellect of everything. Therefore a mind aligned with God’s goodness is a fortiori producer of truth.
For Aquinas, the essence of being and truth might be his adequation to the object. But if I see an apple, I only have access to the qualities that the apple has, such as redness, freshness, sourness, etc. The object conforms to the entity (ens) insofar as its accidents are concerned.
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