In Greek the first word of 1 John designates the Word of Life, who in verse 4 is identified as Jesus Christ. Since the Epistle and the Gospel have the same author, it is permissible to connect this Word of Life with the Word of John 1:1. And no one should object if we equate this Word with him whom Paul calls “the Power of God” and “the Wisdom of God.” This second person of the Trinity is the subject of John’s declaration. Can this eternal Wisdom be heard with the ears, seen with the eyes, and handled with the hands? Is the second person of the Trinity an object of sense? The word hearing comes first; seeing comes second. This discussion will take them in turn.
– Gordon Clark
i) I've discussed this before, but now I'd like to make an addition observation. Where could the "Word of Life" destination come from? Here's a clue:
The words that I have spoken to you are spirit and life (Jn 6:63)
Simon Peter answered him, “Lord, to whom shall we go? You have the words of eternal life (Jn 6:68).
Jesus told the disciples that his spoken words are life. And Peter echoed that statement when he said Jesus had the words of eternal life.
Therefore, it's easy to see why John would use "the Word of Life" as a title for Jesus. And note that this goes back to the Incarnate Son. So, yes, the Incarnate Son could be heard with ears, seen with eyes, and handled with hands. He was visible, audible, and tangible. Indeed, during the course of his ministry, he touched, or was touched by, many people.
ii) In addition, Clark denies what the text explicitly affirms. The text (1 Jn 1:1-3) explicitly asserts the visible, audible, tangible nature of the subject, which Clark proceeds to flatly deny. The text uses the same type of terminology John's Gospel uses in reference to the Incarnate Son (1:14) and the Risen Son (20:24-29). Clark's anti-Incarnational interpretation is heretical. He dehistoricizes John's forceful affirmation, with its allusions to the Incarnation and Resurrection. Clark reduces this to an idea.
iii) Clark doesn't begin with Scripture. Rather, he begins with philosophy. He begins with his rationalistic epistemology. No one who took a passage like 1 Jn 1:1-3 as his starting-point would deny the possibility of sense knowledge. Rather, Clark must deny that in spite of the passage.