Peanuts by Charles Schulz for April 20, 1967

Transcript:

Linus sits on the ground next to Snoopy and reads a book. He says, "'Well! I've often seen a cat without a grin,' thought Alice . . ."<BR><BR> Snoopy smiles. Linus continues, "But a grin without a cat! It's the most curious thing I ever saw in all my life!"<BR><BR> Snoopy disappears, except for his smile.<BR><BR> Snoopy reappears and thinks, "Actually, it's a conditioned reflex!"<BR><BR>