Why is carbene an electrophile?
Around the carbon in dichlorocarbene there 6 electrons; it would "like" to have 8.
The carbon in methane has 6 electrons. Two are inner shell and do not participate in bonding. Each hydrogen atom contributes 1 electron, and the carbon has 8 electrons to form 4 covalent bonds.
Now consider carbene, or dichlorocarbene,
Note that in all of these examples the carbon remains neutral.