The Westminster Confession of Faith declares the value of logic for understanding truth, saying, “The whole counsel of God concerning all things necessary for His own glory, man’s salvation, faith and life, is either expressly set down in Scripture, or by good and necessary consequence may be deduced from Scripture.” The truth that Jesus is God is set down in John 1:1, 8:58, Titus 2:13, and Hebrews 1:8, as is the truth that Jesus is Man, in John 8:40, Acts 2:22, and Hebrews 2:14.
But the truth that Jesus is both God and Man is deduced “by good and necessary consequence” from those statements set down expressly, by a rule of inference called conjunction (we know P, we know Q, therefore we know P and Q). This may sound obvious enough, but the nature of that conjunction (eg. was Jesus one Person in two natures, divine and human, or only of or from two natures?) took several centuries for the church to apprehend and set down in creeds, such as the Definition of Chalcedon.