Suppressing instincts. That's ironic. Addiction isn't a moment-to-moment battle for him, but it is day-to-day. If anything is a suppression of harsh instincts, it's staying sober. But Sherlock does not say as much now. Instead he just hums, thoughtfully, and walks past Christopher to look at another part of the museum entirely.

"You'll find I don't have any instincts towards familial bonds or camaraderie. I'm sorry to say you'll be disappointed on that score."