1. A method for healing an information technology (IT) system, the method comprising: receiving, by a cognitive computing hardware system, an error log from an IT system, wherein the error log comprises a record of one or more errors currently being detected by at least one sensor in the IT system; receiving, by the cognitive computing hardware system, an error history log, wherein the error history log describes a history of past errors that have occurred in the IT system; receiving, by the cognitive computing hardware system, a listing of alternative IT systems, wherein the alternative IT systems have been predetermined to have a same functionality as the IT system that is currently experiencing the one or more errors; receiving, by the cognitive computing hardware system, a list of incidents and changes that have occurred on the IT system; receiving, by the cognitive computing hardware system, a record of real-time events from at least one external event server, wherein the real-time events are external to the IT system, and wherein the real-time events impact a performance of the alternative IT systems; generating, by the cognitive computing hardware system, a prioritized set of solutions to heal the IT system, wherein solutions from the prioritized set of solutions are prioritized based on the error history log, the listing of alternative IT systems, and the record of real-time events; transmitting, from the cognitive computing hardware system to the IT system via an implementer system, a highest prioritized solution from the prioritized set of solutions, wherein the highest prioritized solution has a greater probability of healing the one or more errors, that are in the error history log and that are detected by said at least one sensor in the IT system, than any other solution, from the prioritized set of solutions, based on the error history log, the listing of alternative IT systems, and the record of real-time events; and implementing, by the implementer system, the highest prioritized solution from the prioritized set of solutions in order to heal the one or more errors currently being detected by said at least one sensor in the IT system.