“…A good example is the following: for Bernoulli bond percolation on the usual graph , prove that the probability of the origin being connected to ( n ,0,…,0) monotone in n . This problem is still open, except when the parameter is close to 0 or 1 . For oriented percolation on , the probability of the origin being connected to ( m − n , m + n ) is decreasing in n ∈ {0,…, m } for fixed m ; this may be obvious but the proof is not straightforward .…”