Possible Clues:

• Conclusion of Descartes
• Thinking person's conclusion?
• 'Today -- a man'
• "___ the Walrus" (The Beatles)
• '__ the Walrus' (Beatles song)
• 'You bet --!'
• '-- a Rock'
• 'Take me as --'
• "Of this ___ certain"
• '___ Iron Man...'