Observe, record, tabulate, communicate. Use your five senses. Learn to see, learn to hear, learn to feel, learn to smell, and know that by practice alone you can become expert.

The quote compresses a whole method of clinical (and scientific) thinking into a sequence: attend closely to reality (“observe”), preserve it faithfully (“record”), organize it for comparison (“tabulate”), and share it for scrutiny and collective learning (“communicate”). Osler’s insistence on the five senses underscores that expertise begins with trained perception—seeing subtle signs, hearing changes in breath or speech, feeling texture and temperature, even noticing odors—before instruments or abstractions. The final claim, that mastery comes “by practice alone,” frames medicine as a learned skill: judgment is built through repeated encounters, reflection, and disciplined habits, not merely through reading or authority.